Influences of high intracranial pressure on the compliance of respiratory system in dog / 解放军医学杂志

ABSTRACT

Objective To investigate the effect of acute high intracranial pressure on the static pressure-volume curve of dogs' total respiratory system in order to evaluate the relationship between brain injury and respiratory insufficiency.Methods Fourteen dogs were divided into two groups.Animals were anesthetized,paralyzed and mechanical ventilated.The intracranial hypertension in experimental group(n=8)was induced by injecting blood-clots into the right frontal lobe.The other six dogs served as control.The intracranial pressure was monitored by an optical fiber transmitter inserted into the left cerebral hemisphere.The pressure-volume curves of the respiratory system were measured before and after induction of high intracranial pressure by a self-made apparatus consisting of two sealed bottles and a U shaped glass tube.The curves were also measured correspondingly in control group.The static compliance was calculated by equation C=?V/?P.The volume of intracerebral hematoma was calculated.The histopathology of lung was studied under microscope.Results The intracerebral hematoma was located in the right frontal lobe with volume from 4.8-11.5ml(average 8.48ml).The intracranial pressure was elevated from 18.13?5.96mmHg to 46.88?16.42mmHg,which induced a shift of pressure-volume curve to the right in experimental group,while no obvious change was found in control group.Compared to pre-injection,the static compliance of total respiratory system decreased significantly(P